Apparently, global warming is now irreversible. Or, at least, it is if you don’t consider any of the policy options that might, you know, reverse it. As Roger Pielke Jr points out, the study didn’t examine the potential for geoengineering:
Geoengineering to remove carbon dioxide from the atmosphere was not considered in the study. “Ideas about taking the carbon dioxide away after the world puts it in have been proposed, but right now those are very speculative,” said Solomon.
Then only reason geoengineering remains speculative is because the global warming industry is locked into one policy model: mitigation. If adaptation is the red-headed stepchild of global warming research, geoengineering is the unacknowledged bastard, kept tied up in the basement and fed only with a bucket of fish heads.
Meanwhile, the McKinsey Global Initiative has come out with version 2 of its “we can save the world very cheaply” report, which is available if you register and give them your email address via the links here. The fiendish consultants have disabled the ability to cut their charts out, so you’ll have to get a copy for yourself, but their Exhibit 1 shows that all the “affordable” options are to do with energy efficiency, not grand new green energy projects, which are much more expensive and require aggressive carbon pricing (and this needs to be born in mind as well). Furthermore, these are truly global initiatives – something has has to be done everywhere, around the world – as Exhibit 4 makes clear. Something we can do quite affordably may be a different kettle of fish heads for the developing world. If you can’t afford an incandescent lightbulb, you can’t afford an LED lamp, whatever the CO2 abatement potential is. I hope to provide a full response to the McKinsey paper soon.